Termites hold key to man's future homes

To most of the world they are destructive pests, but termites' complex and ingenious homes could revolutionise the way humans live in the future.

A team of British and American scientists has embarked on a three-year study of the giant mounds built by the insects in sub-Saharan Africa to find out how their intricate structure allows a constant temperature to be maintained inside, despite extreme changes outside. Their findings could help humans build more environmentally friendly and cheaper houses.

The mounds are impressive for their size alone: typically they are three metres high, and some as tall as eight metres have been found. They also reach far into the earth, where the insects 'mine' their building materials, carefully selecting each grain of sand they use.

Inside is an intricate lattice of tunnels that draws in fresh air from outside and expels spent air from the nest to prevent the termites from suffocating. So detailed is the design that the nest stays within three degrees of a constant temperature - despite the mercury outside topping 40 C on hot days and dropping below freezing on the coldest nights. The same structure automatically regulates the moisture in the air, and some colonies even add chimneys at heights of 20 metres to control humidity in the hottest regions, such as in Namibia, where the study is based.

The structure finely moderates the living environment of the nest at the centre, where the king and queen are the only termites in a colony of one to two million insects that reproduce.

The mounds also contain 'farms or gardens' of a special fungus found nowhere else on earth which the termites use to break down wood pulp into cellulose for building, and a sugary substance for energy.

The next step could be to find out how the termites manage their waste - because none comes out of the structure.

Biologists are so excited by the mounds that they have labelled them a 'super organism' because they 'dance on the edge of what we would perceive as what's living and what's not,' said Dr Rupert Soar of Loughborough University, which is involved in the study. 'If you get too hot you need to perspire to cool down, or if you're too cold you need to shiver: that's called homeostasis,' he explained. 'What the termites have done is move that homeostatic function from their body to the structure in which they live.'

Lessons learnt from the research would not mean houses in the future being built with tunnels and membranes. Rather, the new knowledge could, for example, be used to design walls which have some of the same properties as termite mounds.

To learn how to do this, mounds will be filled and covered with plaster of Paris and then sliced into half-millimetre-thick slices which will be photographed one by one. Computer technology can then recreate three-dimensional models of the structure. In another sign of the excitement generated by the project, the team will also work with Sir David Attenborough on his next BBC wildlife series. They hope the techniques could not only save energy and money, but also help people build homes in the harshest environments.

The research is funded by £421,000 from the UK's Engineering and Physical Sciences Research Council. Cambridge University and State University of New York are also involved.